I have a socket I bought for my old MD2B flywheel nut. It is almost certainly the same size at 55mm. It is hughmungous! It comes with a 3/4" to 1/2" drive converter so you can use it with a normal socket set. I no longer need it so it is yours for the cost of postage (which might exceed it's cost!) if you want it.
PM me, or use the e-mail address on my profile.
Incidentally, this is a useful tool for MD owners if MarkP decides to buy his own locally. Just PM or e-mail your interest. SWMBO will be delighted to see another bit of my junk disappear.